The present invention is directed to providing broadband signals to a portable user device. More specifically, the present invention is directed to a method and apparatus for providing broadband signals, such as satellite radio signals, to a portable user device, such as a potable digital assistant (PDA), cell phone, etc., using space time coding.
Satellite radio signals are broadcast signals transmitted via a space-based satellite to a receiving device. A satellite radio receiver is a digital radio that receives signals broadcast by a satellite over a satellite radio channel. Satellite radio signals cover a much larger range than terrestrial radio signals. Satellite radio signals typically are broadcast using a 2.3 GHz S band in North America and sharing a 1.4 GHz L band elsewhere.
Satellite radio services are typically offered by business entities as a package of satellite radio channels that require a subscription to access. Such satellite radio channels contain satellite radio content, which can include various types of music, talk, etc. Each satellite radio receiver has a unique electronic serial number (ESN) to identify it. When a user subscribes to a satellite radio service, a subscription is associated with the ESN of user's satellite radio receiver. The ESN of associated with the subscription is then included in an authorization code that is transmitted with the satellite radio signals from the satellite. The satellite radio signals transmitted from the satellite cannot be accessed by receiver whose ESN is not identified in the authorization code. Accordingly, the authorization code is received by satellite radio receivers and allows a receiver identified by its ESN in the authorization code to access the satellite radio content.
Many portable user devices typically use narrowband technology for transmitting and receiving wireless signals. Because satellite radio signals are broadcast at a broadband frequency rather than a narrowband frequency, portable user devices cannot reliably act as receivers for the broadband satellite radio signals.